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941.
The study evaluated the off-line relationship of attention, memory and other cognitive performances with the auditory event-related potentials P3 (P300) and N2. The sample comprised 200 middle-aged construction workers. Verbal, visuomotor and memory tests were administered. Attentional domains were examined using CogniSpeed software. Slowed reaction times in the test of sustained attention (vigilance) were associated with delayed P3 latency (p < 0.001) and decreased P3 amplitude (p = 0.005), as well as with delayed N2 latency (p < 0.001). Visuomotor slowing in Digit Symbol was also related to delayed P3 latency (p = 0.030) and decreased P3 amplitude (p = 0.014). In contrast, mild cognitive impairment, short- and long-term memory, and concentrating or sharing attention with high working memory demands were not related to P3. The results suggest that P3 is linked to attentional performance with low working memory demands rather than to effortful working memory updating, retrieval from memory stores, or mild cognitive impairment.  相似文献   
942.
A commutative BCK-algebra with the relative cancellation property is a commutative BCK-algebra (X;*,0) which satisfies the condition: if ax, ay and x * a = y * a, then x = y. Such BCK-algebras form a variety, and the category of these BCK-algebras is categorically equivalent to the category of Abelian ℓ-groups whose objects are pairs (G, G 0), where G is an Abelian ℓ-group, G 0 is a subset of the positive cone generating G + such that if u, vG 0, then 0 ∨ (u - v) ∈ G 0, and morphisms are ℓ-group homomorphisms h: (G, G 0) → (G′,G0) with f(G 0) ⫅ G0. Our methods in particular cases give known categorical equivalences of Cornish for conical BCK-algebras and of Mundici for bounded commutative BCK-algebras (= MV-algebras). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
943.
The increased risk of falls in the older aged population demands the development of assistive robotic devices capable of effective balance support. For the development and increased user acceptance of such devices, which provide balance support in a human-like way, it is important to understand the simultaneous occurrence of entrainment and sway reduction in human-human interaction. However, sway reduction has not been observed yet during a human touching an external, continuously moving reference, which rather increased human body sway. Therefore, we investigated in 15 healthy young adults (27.20±3.55 years, 6 females) how different simulated sway-responsive interaction partners with different coupling modes affect sway entrainment, sway reduction and relative interpersonal coordination, as well as how these human behaviours differ depending on the individual body schema accuracy. For this, participants were lightly touching a haptic device that either played back an average pre-recorded sway trajectory (“Playback”) or moved based on the sway trajectory simulated by a single-inverted pendulum model with either a positive (Attractor) or negative (Repulsor) coupling to participant's body sway. We found that body sway reduced not only during the Repulsor-interaction, but also during the Playback-interaction. These interactions also showed a relative interpersonal coordination tending more towards an anti-phase relationship, especially the Repulsor. Moreover, the Repulsor led to the strongest sway entrainment. Finally, a better body schema contributed to a reduced body sway in both the “reliable” Repulsor and the “less reliable” Attractor mode. Consequently, a relative interpersonal coordination tending more towards an anti-phase relationship and an accurate body schema are important to facilitate sway reduction.  相似文献   
944.
Stimulus identification and action outcome understanding for a rapid and accurate response selection, play a fundamental role in racquet sports. Here, we investigated the neurodynamics of visual anticipation in tennis manipulating the postural and kinematic information associated with the body of opponents by means of a spatial occlusion protocol. Event Related Potentials (ERPs) were evaluated in two groups of professional tennis players (N = 37) with different levels of expertise, while they observed pictures of opponents and predicted the landing position as fast and accurately as possible. The observed action was manipulated by deleting different body districts of the opponent (legs, ball, racket and arm, trunk). Full body image (no occlusion) was used as control condition. The worst accuracy and the slowest response time were observed in the occlusion of trunk and ball. The former was associated with a reduced amplitude of the ERP components likely linked to body processing (the N1 in the right hemisphere) and visual-motor integration awareness (the pP1), as well as with an increase of the late frontal negativity (the pN2), possibly reflecting an effort by the insula to recover and/or complete the most correct sensory-motor representation. In both occlusions, a decrease in the pP2 may reflect an impairment of decisional processes upon action execution following sensory evidence accumulation. Enhanced amplitude of the P3 and the pN2 components were found in more experienced players, suggesting a greater allocation of resources in the process connecting sensory encoding and response execution, and sensory-motor representation.  相似文献   
945.
Evoked potential studies have demonstrated that musicians have the ability to distinguish musical sounds preattentively and automatically at the temporal, spectral, and spatial levels in more detail. It is however not known whether there is a difference in the early processes of auditory data processing of musicians. The most emphasized and studied early process, especially for neuropsychiatric purposes, is sensory gating. The suppression percentage of the midlatency auditory evoked potential P50, and rarely the N100, wave is used for sensory gating studies. Our aim in this study was to investigate whether there was a difference in the auditory P50 and N100 suppression of control subjects who were professional musicians with no psychiatric problems. 34 professional musicians and 19 non-musicians (the control group) were included in this study. P50 and N100 measurements were taken, the suppression percentage of P50 and N100 was calculated and the results compared. Musicians showed significantly less P50 suppression when compared to non-musicians. There was no significant difference for N100 suppression. What the decreased P50 suppression in musicians when compared to non-musician subjects means, when we also take into account that N100 suppression is not decreased, and how it may contribute to the music perception and production processes of these persons is discussed.  相似文献   
946.
Integrating ethics in design through the value-sensitive design approach   总被引:1,自引:0,他引:1  
The Accreditation Board of Engineering and Technology (ABET) has declared that to achieve accredited status, “engineering programs must demonstrate that their graduates have an understanding of professional and ethical responsibility.” Many engineering professors struggle to integrate this required ethics instruction in technical classes and projects because of the lack of a formalized ethics-in-design approach. However, one methodology developed in human-computer interaction research, the Value-Sensitive Design approach, can serve as an engineering education tool which bridges the gap between design and ethics for many engineering disciplines. The three major components of Value-Sensitive Design, conceptual, technical, and empirical, exemplified through a case study which focuses on the development of a command and control supervisory interface for a military cruise missile.  相似文献   
947.
The neural bases of timing mechanisms in the second-to-minute range are currently investigated using multidisciplinary approaches. This paper documents the involvement of the supplementary motor area (SMA) in the encoding of target durations by reporting convergent fMRI data from motor and perceptual timing tasks. Event-related fMRI was used in two temporal procedures, involving (1) the production of an accurate interval as compared to an accurate force, and (2) a dual-task of time and colour discrimination with parametric manipulation of the level of attention attributed to each parameter. The first study revealed greater activation of the SMA proper in skilful control of time compared to force. The second showed that increasing attentional allocation to time increased activity in a cortico-striatal network including the pre-SMA (in contrast with the occipital cortex for increasing attention to colour). Further, the SMA proper was sensitive to the attentional modulation cued prior to the time processing period. Taken together, these data and related literature suggest that the SMA plays a key role in time processing as part of the striato-cortical pathway previously identified by animal studies, human neuropsychology and neuroimaging.  相似文献   
948.
Many studies have observed phonetic and phonological differences between function words and content words. However, as many of the most commonly cited function words are also very high in frequency, it is unclear whether these differences are the result of syntactic category or word frequency. This study attempts to determine whether syntactically defined function words are indeed phonologically and phonetically reduced or assimilated when word frequency is balanced. Three experiments were designed to distinguish the relative contributions of the factors of category and frequency on phonetic and phonological reduction and assimilation. Overall results suggest that syntactic category and word frequency interact with phonetic and phonological processes in a more complex way than previously believed. Experiment 1 measured final t/d dropping, a reduction process, using electropalatography (EPG). Experiment 2 examined vowel reduction using acoustic measures. In Experiment 3, palatalization, an assimilation process, was examined using EPG. Results showed that t/d dropping responds to the factor of syntactic category, whereas palatalization is affected by word frequency; vowel reduction responded to both factors, with a dominant syntactic category effect and a secondary within-category frequency effect. The implications of these findings for models of lexical representation and theories of language acquisition are discussed.  相似文献   
949.
The relationship between test results from the Meta-Contrast Technique (MCT) and self-reports from Karolinska Scales of Personality (KSP), or the State Trait Anxiety Inventory (STAI-T), was investigated in 100 healthy women. Additionally, it was investigated whether age and cognitive abilities influenced the reports of picture recognition thresholds in the MCT. The results showed no agreement between the different ways to assess anxiety and defensiveness. However, age consistently predicted later reports of the perceptual recognition thresholds A1 (the car), A2 (the face) and C-phase. The WAIS-R Digit Symbol Score predicted earlier reporting of the recognition thresholds A1 and A2, but did not predict the final criteria for correct recognition (C-phase). The KSP aggression factor only predicted an earlier report of recognition threshold A2. The absence of a simple relationship between the different ways to assess anxiety and defensiveness, and the observed relationships regarding perceptual threshold levels, corroborates previous findings.  相似文献   
950.
Mel Gibson’s repeated claim for the accuracy of his powerful and popular film, The Passion of the Christ, inevitably raises the question: Where’s the history here? A close analysis leads to these conclusions: Gibson provides no context for understanding the brutality suffered by Jesus in this film, why anyone hated him or followed him. Gibson relies on medieval speculations and 19th century visions for most of the plot and many of the scenes. He whitewashes the Roman prefect Pontius Pilate and presents Pilate’s wife as a crypto-follower of Jesus. He demonizes most of the Jewish leaders, especially the high priest Caiaphas, makes Mary, Jesus’ mother, the unhistorical focus of very many scenes, and ignores the historical Jesus’ critical actions, prophetic social critique, and profound concern for the poor and marginal.  相似文献   
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